commit c0e01d5d8f15c085236df184e5bc3d79a8b700cd upstream.

struct compat_ucontext * is a 64-bit pointer, so we need to use a
compat_uptr_t instead to avoid declaring a structure incompatible with
what AArch32 userspace expects.

Reported-by: Edmund Grimley-Evans <Edmund.Grimley-Evans@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The kernel's internal definition of ELF_NGREG uses struct pt_regs, which
means that we disagree with userspace on the size of coredumps since
glibc correctly uses the user-visible struct user_pt_regs.

This patch fixes our ELF_NGREG definition to use struct user_pt_regs
and introduces our own ELF_CORE_COPY_REGS to convert between the user
and kernel structure definitions.

Cc: <stable@vger.kernel.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

Pull arm64 fixes from Catalin Marinas:
 - Page protection fixes, including proper PAGE_NONE handling
 - Timezone vdso sequence counting fix
 - Additional compat syscall wiring

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/cmarinas/linux-aarch64:
  arm64: compat: add syscall table entries for new syscalls
  arm64: mm: introduce present, faulting entries for PAGE_NONE
  arm64: mm: only wrprotect clean ptes if they are present
  arm64: vdso: remove broken, redundant sequence counting for timezones

There have been a number of new syscalls introduced to arch/arm/ since
the compat layer was implemented for arm64, so add pointers to the
relevant functions to the compat syscall table.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

if_changed (used by the *.dts->*.dtc rule) rebuilds files if they aren't
contained in $(targets). (make V=2 indicates this). Add $(dtb-y) to
$(targets) to prevent *.dtb from always being rebuilt. Note

This fixes a regression introduced by the .dtb rule rework in da4cbc6
"arm64: use new common dtc rule", although since arm64 doesn't actually
have any *.dts yet, this isn't a critical issue.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Rob Herring <rob.herring@calxeda.com>

This is mostly a port of dbf62d50067e ("ARM: mm: introduce L_PTE_VALID
for page table entries") and 26ffd0d43b18 ("ARM: mm: introduce present,
faulting entries for PAGE_NONE") from ARM, which makes use of present,
faulting page table entries for page table entries mapped as PROT_NONE.

The main difference with this implementation is that we can make use of
the two pte type bits in order to avoid allocating a software bit for
identifying PROT_NONE pages, instead reserving the 10b suffix for these
types of mappings.

This is required to prevent users from accessing such pages via syscalls
such as read/write over a pipe.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

Marking non-present ptes as read-only can corrupt file ptes, breaking
things like swap and file mappings.

This patch ensures that we only manipulate user pte bits when the pte
is marked present.

Cc: <stable@vger.kernel.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

This patch is an arm64 version of ce73ec6db47a ("powerpc/vdso: Remove
redundant locking in update_vsyscall_tz()").

Timezone data is not protected, so the sequence counter is not required
to ensure consistency. Furthermore, having multiple paths updating the
counter leads to a race between update_vsyscall and update_vsyscall_tz,
so remove the timezone sequence counting from both the kernel and the
vdso.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

Pull ARM64 fixes from Catalin Marinas:
 - Missing include in asm/compat.h.
 - Kconfig updates.

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/cmarinas/linux-aarch64:
  arm64: Always select ARM_AMBA and GENERIC_GPIO
  arm64: Keep the ARM64 Kconfig selects sorted
  arm64: Include linux/ptrace.h in asm/compat.h

Needed for most SoCs.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>